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Antithrombotic Therapy to Ameliorate Complications of COVID-19 ( ATTACC )

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT04372589
Recruitment Status : Not yet recruiting
First Posted : May 4, 2020
Last Update Posted : May 12, 2020
University Health Network, Toronto
Hopital Montfort
Hamilton Health Sciences Corporation
Information provided by (Responsible Party):
University of Manitoba

Brief Summary:
The purpose of the study is to evaluate the efficacy of therapeutic-dose parenteral heparin versus usual care in hospitalized COVID-19 patients (e.g. reduced intubation, mortality).

Condition or disease Intervention/treatment Phase
COVID-19 Heparin Pneumonia Anticoagulant Drug: Heparin Not Applicable

Detailed Description:

This is a prospective, open-label, randomized, multicentre, adaptive clinical trial to establish whether therapeutic-dose parenteral anticoagulation improves outcomes for COVID-19 positive participants (e.g., reduces intubation or mortality, etc.).

Participants will be randomized either to the investigational arm (to get therapeutic anticoagulation for 14 days or until hospital discharge/liberation from supplemental oxygen), or to the control arm (to get usual care which will include thromboprophylactic dose anticoagulation according to local practice).

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 3000 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Antithrombotic Therapy to Ameliorate Complications of COVID-19
Estimated Study Start Date : May 2020
Estimated Primary Completion Date : January 2021
Estimated Study Completion Date : January 2021

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Blood Thinners

Arm Intervention/treatment
Experimental: Investigational arm
Participants randomized to the investigational arm will receive therapeutic anticoagulation for 14 days (or until hospital discharge or liberation from supplemental oxygen >24 hours if previously required, whichever comes first) with heparin, with preference for subcutaneous low molecular weight heparin (enoxaparin preferred, although dalteparin or tinzaparin are also acceptable, as available) if no contraindication is present; alternatively, intravenous unfractionated heparin infusion may be used.
Drug: Heparin

Low molecular weight heparin (LMWH) Preferred therapeutic anticoagulant is enoxaparin. Generally regimens: 1.5 mg/kg subcutaneous once daily or 1 mg/kg subcutaneous twice daily. Alternatively, other subcutaneous LMWH used, including tinzaparin (175 anti-Xa IU/kg subcutaneous once daily) or dalteparin (200 IU/kg subcutaneous once daily or 100 IU/kg subcutaneous twice a day).

Unfractionated heparin (UFH) Commenced, administered, and monitored according to local hospital policy, and guidelines that are used for the treatment of venous thromboembolism (i.e. not for acute coronary syndrome). Intravenous infusion of UFH is according to total body weight and pragmatically adjusted according to local institutional policy to achieve an activated partial thromboplastin time (aPTT) of 1.5-2.5x the reference value. If UFH is used, the availability of a local hospital policy that has specifies an aPTT target in this range or an anti-Xa value is a requirement.

No Intervention: Control arm
Participants will receive usual care of thromboprophylactic dose anticoagulation according to local practice.

Primary Outcome Measures :
  1. Intubation and mortality [ Time Frame: 30 days ]
    Any need for invasive mechanical ventilation or mechanical ventilation, and occurrence of death within 30 days following randomization

Secondary Outcome Measures :
  1. Hospital-free days [ Time Frame: 30 days ]
    Days alive without staying overnight at a hospital 30 days post randomization

  2. Thrombocytopenia [ Time Frame: 30 days ]
    Any thrombocytopenia attributed to Heparin within 30 days following randomization

  3. Bleeding [ Time Frame: 30 days ]
    If patient experiences bleeding (1) in a critical area or organ, such as intracranial, intraspinal, intraocular, retroperitoneal, intraarticular or pericardial, or intramuscular with compartment syndrome 30 days after randomization; and/or (2) causing a fall in hemoglobin level of ≥20 g/L, or leading to transfusion of 2 or more units of whole blood or red cells.

  4. Transfusion [ Time Frame: 30 days ]
    Transfusion of 2 or more more units of whole blood or red cells due to hemoglobin level of ≥20 g/L within 30 days following randomization

  5. ICU-free days [ Time Frame: 30 days ]
    Whether patient was admitted to the ICU within 30 days following randomization

  6. Ventilator-free days [ Time Frame: 30 days ]
    Number of days alive without the use of a ventilator 30 days following randomization.

  7. Type of ventilator used [ Time Frame: 30 days ]
    Whether or not patient needed non-invasive mechanical ventilation or high flow nasal cannula 30 days following randomization

  8. Organ support-free [ Time Frame: 21 days ]
    Organ support-free days 21 days after randomization

  9. Myocardial infarction [ Time Frame: 30 days and 90 days ]
    Whether patients experience a myocardial infarction 30 days and 90 days from randomization

  10. Ischaemic stroke [ Time Frame: 30 days and 90 days ]
    Whether patients experience an ischaemic stroke 30 days and 90 days from randomization.

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

1. Patients ≥18 years of age providing (possibly through a substitute decision maker) informed consent who require hospitalization anticipated to last ≥72 hours, with microbiologically-confirmed COVID-19, enrolled < 72 hours of hospital admission or of COVID-19 confirmation

Exclusion Criteria:

  1. Receiving invasive mechanical ventilation
  2. Patients for whom the intent is to not use pharmacologic thromboprophylaxis
  3. Active bleeding
  4. Risk factors for bleeding, including:

    1. intracranial surgery or stroke within 3 months;
    2. history of intracerebral arteriovenous malformation;
    3. cerebral aneurysm or mass lesions of the central nervous system;
    4. intracranial malignancy
    5. history of intracranial bleeding
    6. history of bleeding diatheses (e.g., hemophilia)
    7. history of gastrointestinal bleeding within previous 3 months
    8. thrombolysis within the previous 7 days
    9. presence of an epidural or spinal catheter
    10. recent major surgery <14 days
    11. uncontrolled hypertension (sBP >200 mmHg, dBP >120 mmHg)
    12. other physician-perceived contraindications to anticoagulation
  5. Platelet count <50 x10^9/L, INR >2.0, or baseline aPTT >50
  6. Hemoglobin <80 g/L (to minimize the likelihood of requiring red blood cell transfusion if potential bleeding were to occur)
  7. Acute or subacute bacterial endocarditis
  8. History of heparin induced thrombocytopenia (HIT) or other heparin allergy including hypersensitivity
  9. Current use of dual antiplatelet therapy
  10. Patients with an independent indication for therapeutic anticoagulation
  11. Patients in whom imminent demise is anticipated and there is no commitment to active ongoing intervention
  12. Pregnancy
  13. Anticipated transfer to another hospital that is not a study site within 72 hours
  14. Enrollment in other trials related to anticoagulation or antiplatelet therapy

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT04372589

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Contact: Ryan Zarychanski, MD 204-787-2993

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Canada, Ontario
Ottawa Hospital
Ottawa, Ontario, Canada, K1H 8L6
Contact: Marc Carrier, MD    613-737-8899 ext 73034   
Sunnybrook Research Institute
Toronto, Ontario, Canada, M4N 3M5
Contact: Jean-Philippe Galanaud, MD    416-480-5953   
Toronto General Hospital
Toronto, Ontario, Canada, M5G 2C4
Contact: Ewan Goligher, MD    416-586-8449   
Contact: Patrick Lawler    416-340-3141   
Sponsors and Collaborators
University of Manitoba
University Health Network, Toronto
Hopital Montfort
Hamilton Health Sciences Corporation
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Responsible Party: University of Manitoba Identifier: NCT04372589    
Other Study ID Numbers: ATTACC
OZM-113 ( Other Identifier: Ozmosis Research Inc )
First Posted: May 4, 2020    Key Record Dates
Last Update Posted: May 12, 2020
Last Verified: April 2020

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Additional relevant MeSH terms:
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Lung Diseases
Respiratory Tract Diseases
Respiratory Tract Infections
Fibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action